The tiny forefoot of a lizard of the genus Anolis was trapped in amber about 15 to 20 million years ago. Every detail of this rare fossil is visible under the microscope. But the seemingly very good condition is deceptive: The bone is largely decomposed and chemically transformed, very little of the original structure remains. The results provide important clues as to what exactly happens during fossilization.

Source: Rare lizard fossil preserved in amber